Continuous twister and feeder mechanism for brush machines or the like



Dec. 8, 1964 .1. T. GELARDI 3,160,440

CONTINUOUS TWISTER AND FEEDER MECHANISM FOR BRUSH MACHINES OR THE LIKE Filed March 1, 1961 4 Sheets-Sheet l lllllll I"! ||||||1||||||||||| J11lliilllllllhlillllllllllllllllllliiillllllllllllllHl mum" INVENTOR. JOSEPH T. GELARDI ATTORNEY Dec. 8, 1964 .1. T. GELARDI 3,160,440

CONTINUOUS TWISTER AND FEEDER MECHANISM FOR BRUSH MACHINES OR THE LIKE Filed March 1, 1961 4 Sheets-Sheet 2 F1 g. L 65 INVENTOR.

JOSEPH T. GELARDI ATTORNEY RDI 3,160,440 FEEDER MECHANISM Dec. 8, 1964 J. T. GELA CONTINUOUS TWISTER AND FOR BRUSH MACHINES THE LIKE 4 Sheets-Sheet 5 Filed March 1, 1961 INVENTOR JOSEPH T. GELARDI C/"Z'j H ATTORNEY Dec. 8, 1964 J. GELARDI 3,

CONTI US S R AND DER MECHANISM F0 BRU MACHINES THE LIKE Filed March 1, 1961 4 Sheets-Sheet 4 INVENTOR JOSEPH T. GELARDI ATTORNEY United States Patent CONTWUQUS TWETER AND FEEDER MEC Ar NISM FUR BRUSH MACHHJES GK THE LHKE Joseph T. Gelardi, Yonkers, N.Y., assignor to American Brush Machinery (10., End, Mount Vernon, Nil-L, a corporation of New York Filed Mar. l, 1961, Ser. No. 92,657 22 Claims. (ill. 3tlti2) This invention relates in general to automatic machines for making cylindrical brushes or the like in which transnovel structures which include (1) a novel wire twisting device that acts against the bristles of a brush-like article rather than the wires thereof; (2) a novel twister-feeder system which is operable to produce continuous twisted brush-like articles that are unlimited in length; (3) a novel wire twister-feed drive device in which the wires of a brush-like article are simultaneously twisted around and driven along their longitudinal axis by forces exerted on bristles held thereinbetween by the twist formed therein; and (4) a novel wire and bristle feeder structure in which the bristles for a twisted brush-like article are deposited directly into the initial standing twist in the wires thereof. The invention is also characterized by other novel structures and structural relationships as set forth in later paragraphs of this document. Although the invention is described herein with particular reference to brushes and brush making machines, it should be understood that the invention is by no means limited to such applications. The invention can also be used to make Christmas tree decorations, dusters, mops, or any other article in which relatively short transverse members are held in spaced relation between relatively long, twisted longitudinal members. For sake of clarity, however, the explanation is limited to brushes with the understanding that the word brush means any brush-like article, and that the word bristle means any relatively short transverse member, however soft, and that the word wire means any relatively long twistable member, however rigid.

Many different machines and methods for producing twisted brushes have been devised in the past, as shown, for example, in US. Patent No. 2,742,327, which issued to Theodore Marks on April 17, 1956 for a Fully Automatic Machine for Making Brushes. In these prior art machines, cylindrical twisted brushes were formed by (l) grasping the ends of parallel wire strands in the chuck of a reciprocating feed carriage, (2) moving the feed carriage to draw out lengths of wire corresponding to a desired brush body length, (3) laying bristles between the wires during the wire feed period, the bristles being held in place between the parallel Wires by tension thereinbetween, (4) rotating the chuck, either during or after the linear feed stroke, to twist the wires together, (5) cutting olf the length of twisted wire and dropping the twisted brush body out of the machine, (6) holding the clipped wire ends in position to be grasped for the next feed stroke, (7) returning the reciprocating carriage to the clipped wire ends, and (8) grasping the clipped wire ends and repeating the feed-twist-cut sequence to form another twisted brush body.

Although these prior art machines were quite accurate and eiiicient in performing their multiple functions, they suffered from all the disadvantages that are inherent in intermittently operated reciprocating machines. Accordingly, one object of this invention is to provide a brush making machine in which twisted brushes are formed by machine processes.

3,160,440 Patented Dec. 8, 1964 Furthermore, these prior art machines were limited with respect to maximum brush length, and could only produce as single, fixed brush length in any given production run. Therefore, another object of this invention is to provide a brush making machine which is unlimited with respect to maximum brush length and which can produce brushes of different lengths in a single production run.

Moreover, the production speed of the prior art machines was limited to a relatively low level by the intermittent reciprocating mechanisms thereof and by the complex sequence of operations required to produce brushes therein. Accordingly, another object of this invention is to provide a brush making machine which is adapted to produce twisted brushes faster than heretofore possible in the art. Y

in addition, the prior art machines required relatively complex timing mechanisms to actuate the various parts thereof in the complex sequence of operations required to produce brushes therein. Accordingly, another object of this invention is to provide a brush making machine in which twisted brushes are formed by a continuous, selftiming process rather than by a sequence of discrete, independent processes which must be synchronized by a separate timing mechanism.

Furthermore, the prior art machines were relatively complex in structure, relatively difiicult to adjust, and correspondingly difficult to maintain. Accordingly, another object of this invention is to provide a brush making machine which is simpler in structure, easier to adjust, and easier to maintain than the machines heretofore known in the art. 7

Also, the prior art machines were relatively costly in manufacture, relatively short-lived in operation, and relatively expensive to maintain. Accordingly, another object of this invention is to provide a brush making machine which is lower in cost, more durable in operation, and less expensive to maintain than the machines heretofore known in the art.

Additional objects and advantages of this invention will become apparent to those skilled in the art from the following discussion of several illustrative embodiments thereof, which will be described in connection with the attached drawings, in which:

FIG. 1 is an elevation view of the wire twisting and feeder portions of a brush making machine in accordance with this invention;

FIG. 2 is an elevation section showing the brush twisting-feed drive arrangement in the embodiment of FIG. 1;

FIG. 3A is an axial section showing a stationary wire twisting and feed drive element which utilizes air jets to produce simultaneous twisting and feeding forces;

FIG. 3B is a radial section of the device shown in FIG. 3A; a

FIG. 4 is an axial section showing a first alternate set of brush twisting and feed drive elements which can be used in place of those shown in FIG. 2;

FIG. 5 is an axial section showing a unitary brush twisting-feed drive element which can be used in place of those shown in FIG. 2;

FIG. 6 is an axial section showing a second alternate set of brush twisting and feed drive elements which can be used in place of those shown in FIG. 2;

FIG. 7 is a perspective showing a linear fin structure which can be used in place of the rod structures shown in FIGS. 2 and 4; v

FIG. 8 is an axial section showing a spiral fin structure which can be used in place of the helical screws shown in FIGS. 2, 4, and 5;

FIG. 9A is a diagrammatic radial section showing the brush twisting and feed drive elements of FIG. 2 with a pair of untwisted longitudinal brush wires and lateral brush bristles in the center thereof;

FIG. 9B shows the elements of FIG. 9A with the rotatable rods thereof turned 90 degrees counterclockwise and the helical screw thereof held stationary;

FIG. 9C shows the elements of FIG. 913 after an additional 100 degrees of counterclockwise rotation;

FIG. 9D shows the elements of FIG. 90 after an additional 230 of counterclockwise rotationg' FIG. 10 is an enlarged elevation view of the bristle and wire feed mechanism shown in FIG. 1;

FIG. 11 is an elevation view of one of the wire feed jaws shown in FIG. 10; and

FIG. 12 is a plan view of both of the wire feed jaws shown in FIG. 10.

In general terms, the basic feature of this invention comprises a hollow wire twisting element adaptedv to twist the wires of a cylindrical brushbody passing therethrough. This twisting element can be embodied in a variety of physical forms: it can comprise (1) a rotatable cylindrical shell containing a helical wire screw rigidly attached therewithin, (2) a rotatable cylindrical shell containing a pair of stiff rods running longitudinally through the interior thereof, (3) a rotatable cylindrical shell containing inwardly projecting longitudinal fins, (4) a pair of stiff rods connected together at opposing ends by a pair of rotatable washers, (5) a rotatable cylindrical shell containing an inwardly projecting spiral fin, (6) a hollow motor structure, sans armature, adapted. to produce a rotating magnetic field, (7) a fixed cylindrical shell having tangentially-directed air channels through which air jets can be blown, (8) a rotatable cylindrical shell which is substantially smaller in diameter than the brush body, whereby the bristles of the brush body are constricted when driven thereth rough such that rotary forces can be applied to the matted bristles from the smooth interior surface of the shell, and (9) any other structure adapted to admit a brush body and to. apply rotary forces to the wires thereof.

The wire twisting element of this invention can exert its twisting forces against any convenient reacting memser which opposes rotary forces coupled to wires of a rush body. This reacting member can comprise a fixed wire guide structure through which the wires for a brush Jody are drawn, or it can comprise a second wire twisting element which applies rotary forces to the brush wires 11 opposition to the rotary forces developed by the first vire twisting element.

In accordance with a second general aspect of this nvention, the wiretwisting element thereof is preferably adapted to simultaneously exert rotary twisting forces and longitudinal feed forces on the wires of a brush body :hrough the bristles thereof. This feature of the inveniion can be embodied in a rotating helical screw or spiral in structure that works against a fixed wire guide struczure, or in a rotating helical screw that works against,

mother rotating helical screw, or, in a rotating rod or in structure that works against a stationary helical screw, 3r in a rotating helical screw that works against a rotatng rod or fin structure or in an air-jet structrue in which [if jets are directed both tangentially and longitudinally lgainst the brush body.

In accordance with a third general aspect of this inlention, the wire twisting elements thereof are preferably employed in a progressive twisting battery comprising a lurality of twisting elements adapted to receive a comnon brush body, each twisting element being operable 0 increase the twist in the brush body by a predeternined increment of twist to produce a final twist which s approximately equal to the sum of said increments.

In accordance with a fourth general aspect of this in- 'ention, the first stage of a progressive twisting battery )referably comprises a first rotary wire twisting element vorking against a fixed wire guide structure and the econd stage thereof comprises a second rotary wire twisting element working against said first rotary wire twisting element. 7

In accordance with a fifth general aspect of this invention, the fixed wire guide structure thereof preferably comprises wire guide channels formed in the wire feed jaws from which the wires for a brush body are drawn, the jaws being adapted to oppose thetwisting forces applied to the wires of the brush body by a wire twisting element.

In accordance with a sixth general aspect of this invention, the wire feed jaws thereof are preferably spaced with respect to each other, and the bristles for a brush body are preferably inserted between the wires thereof in the space separating the feed jaws therefor.

In accordance with a seventh general aspect of this invention, the wires for a brush body are preferably skewed with respect to each other at they feed jaws from which they are drawn to oppose the twisting forces applied to the wires by a wire twisting element.

In accordance with an eighth general aspect of this invention, the wire guide channels formed in the wire feed jaws thereof are preferably curved in one plane to follow the natural curvature produced by a wire twisting element in the wires drawn therethrough.

In accordance with a ninth general aspect of this invention, the wire guide channels formed in the wire feed jaws thereof are preferably curved in one plane to follow the natural curvature produced by a wire twisting elemerit in the wires drawn therethrough and skewed with respect to each other in a different plane to oppose the twisting forces applied to said wires by said twisting element.

And in accordance with a tenth general aspect of this invention, a brush making machine is preferably formed by combining the spaced wire feed jaws, bristle feeder, and progressive twisting battery of this invention with a bristle trimmer and wire cutter as shown in FIG. 1. Referring to FIG. 1, continuous wires 20 and 21 are preferably, although not necessarily, driven from storage reels, not shown, into corresponding guide tubes 22 and 23 by friction drive rollers 24 and 25, which are rotated by means not shown in synchronism with each other to produce a desired wire feed rate. Friction drive rollers 24 and 25 are pressed against their respective wires, the wires being supported by idler rollers 26 and 27. Guide tubes 22' and 23 keep their respective wires from buckling under the driving force, and deliver their respective wires to a pair of spaced wire feed jaws 28 and 29. Structural elements 22 through 27 can be madeof any suitable material, and the means for driving rollers 24 and 25 can be any suitable rotary drive means, many of which are well known to those skilled in the art. 7

It should be noted here that the above described wire feed drive is not essential tothis invention because wire feed forces are developed in the wire twisting elements, and these forces can be used to draw wires 20 and 21 from their respective feed rollers without any assistance. In applications where the brush wires are relatively large, however, or the brush bristles relatively soft, it is preferable to use a separate wire feed drive as shown. In other applications, however, it will be preferable to use the wire feed forces from the twisting elements alone because they have the virtue of being self-synchronized. The separate wire feed drive can always be eliminated by making the contact area between the wire twisting elements and the brush bristles large enough for the particular feed load conditions involved in any given application of the invention. The separate wire feed drive is, however, essential in embodiments which use wire twist i-ng elements that do not develop wire feed forces; 7

The bristles for the brush body are laid between wires 24D and 21 in the space separating jaws 28 and 29 by a picker wheel-pin wheel combination similar to those used in the prior art machines. If desired a multi-slotted wheel may be used in place of the picker-pin wheel combination, the two being functionally equivalent. Suitable bristles 30 are stored in a hopper 31, which may be gravity fed, as shown, but which preferably includes means not shown for applying a feed force to the bristles therein. Bristles 30 are removed from hopper 31 by a rotating picker wheel 32 which is relatively wide in its axial dimen- "sion and which contains a picker slot 33 cut into the periphery thereof. Picker slot 33 is preferably fitted with an adjustable bottom 3 5 which can be raised or lowered to change the bristle capacity of the picker slot 33.

With each revolution of picker wheel 32, picker slot 33 moves across the open end of hopper 31 and receives a charge of bristles which it subsequently dumps on the inclined portion of a bristle guide surface 35. The bristles are then picked up by a dual pin wheel whose symmetrical wheel members are arranged to overlap a portion of picker wheel 32, and whose pins sweep past the bottom of the inclined portion of bristle guide surface 35. Only one half of the pin wheel structure is shown-in the drawings (wheel 36 and its associated pins 37) but it will be understood by those skilled in the art that the assembly contains another wheel, not shown, which is identical to wheel 36, and which is mounted on the same shaft with its pins in alignment with pins 37.

The pins of the pin wheel assembly pick up the bristles dumped out of the picker slot 33 and carry them downward along the lower curved portion of guide surface 35, which merges with a pair of bristle guide rails at its lower ter line of the machine, although smaller or larger inclinations can be used, depending on the application. In this particular embodiment wires 20 and 21 are delivered to their respective jaws by wire guide tubes 22 and 23, which are also rigidly attached to frame members 39 and 4d. The outlet end of the wire feed jaws is placed slightly forward of the center thereof, where center is taken to mean the point on the curvature where the tangent to the curve is horizontal, as indicated by the letter 0 in FIG. 11. The end point is preferably located at the point where the wire curvature begins to deviate substantially from radius r, and this point, which is defined in FIG. 11 by the angle-g5, is also dependent on the specific parameters in any given application. I

The wire guide channels of the two jaws are skewed with respect to each other so as to oppose the twisting of the wires, as shown in FIG. 12. This skewing serves three purposes, (1) it presses the wires against the sides of their respective guide channels so that they will not slip out when the machine is stopped, (2) it prevents the twisting forces from being communicated back into the wire storage reels, and (3) it spreads the first twist in the wires to form a pocket in which the bristles can be laid.

end. Only one guide rail (rail 33) is shown in the drawings, but it will be understood by those skilled in the art that a second guide rail, not shown, is mounted parallel to guide rail 38. The bristles are driven along the guide rails and are released at the point where the pins of the pin wheel assembly rise above the bristle guide rails.

Picker wheel 32. and pin wheel 36 are driven, by means not shown, at some predetermined speed to lay bristles between wires 20 and 21 at the desired rate, which is dependent on the wire feed rate and the bristle density required in the finished brush. The selection of these speeds, however, is well known to those skilled in the art, as are the other adjustments or structural modifications required to lay bristles at any desired rate between wires 20 and 21. Asthus far described, the bristle feed mechanism is similar to the prior art structures, and any suitable prior art materials or techniques can be employed therein. In accordance with this invention the release point for the bristles is located in the space separating wire feed jaws 28 and 29, preferably at or slightly forward of the vertical centerline thereof, as more clearly shown in FIG. 10. The purpose behind this particular location will become more apparent from a detailed description of wire feed jaws 28 and 29, which are adapted to act as reacting members to twisting forces developed on wires 2t! and 21 by a wire twisting element. laws 28 and 2% are rigidly attached to fixed frame members 39 and at which are rigidly attached to or form a part of the frame structure, not shown, which supports the bristle feed and wiredrive assemblies. Each of the jaws has a wire guide channel formed in the surface thereof, as indicated by the dotted lines which follow the surface curvature of the jaws in the elevation view of FIGS. 10 and 11, and which are skewed with respect to each other in the plan View of FIG. 12.

The curvature r of these wire guide channels is preferably selected to match the natural curvature that would be produced in wires 21 and 29 at the normal twisting rate thereof. The exact value of curvature used will, of course depend on the specific parameters for any given application, such as the dimensions and resiliency of the wires, wire feed rate, the magnitude of the twisting force, and the like- As shown in FIG. 11, the curvature of the wire guide channels is modified at the wire inlet end to match the angle at which the wires 2% and 21 are delivered to their respective jaws. These angles are preferably in the neighborhood of 45 above or below the horizontal cen- The angle of skew will also vary according to specific conditions, but it should be oriented to oppose the twist of the wires. It should be noted here that the structure of jaws 23 and29 is identical; the required skew angle is produced by an inverted relation'between two identical jaw structures each of whose wire guide channels are inclined at the same angle 6 to the longitudinal center line.

The bristles are laid in the pocket formed by the first standing twist in wires 20 and 21 at or slightly forward of the center of jaws 28 and 29, which obviates any tendency of the bristles to slide backward on the downward curve of lower jaw 2%. This is done by adjusting pin wheel 36 so that pins 37 rise above bristle guide rail 38 at the center of the jaws. The exact point of release is not critical, but it should not be so far forward that pins 37 catch on the bristles laid in the pocket by a preceding pin. It will be noted that the standing twists in the wire get progressively smaller until they reach a relatively tight twist at some distance forward of the jaws. This smooth progression provides a natural feeder mechanism for feeding the bristles smoothly and uniformly into the tight twist. This progression, which is enhanced by the spreading eifect of the skewed wire guide chan nels, prevents the bristles from being driven backward when pinched between the twisted wires.

It should be noted here that the bristle and wire feeder portions of this invention can be used, if desired, in the prior art machines to simplify the structure and improve the performance thereof. In this case the picker wheel andpin wheel structures would be operated intermittently, in synchronism with thereciprocating carriage, whose chuck would be rotated during the feed stroke to twist the wires as they were drawn from the feed jaws. The skewed guide channels and twisted Wires would provide a natural vise for holding the clipped end of the brush, butif further support were needed it could be provided by a collar structure somewhat smaller in diameter than the brush body. This collar could be mounted between the feed jaws and the wire cutting dies to hold the clipped end of the brush in position to be grasped by the reciproeating chuck for the next feed-twist-cut operation.

-In accordance with the preferred operation, however, the wires emerging from jaws 28 and 29 are twisted together by rotary forces applied to the bristles thereof in a two-stage progressive twisting battery of this invention, to be described later, which produces a desired degree of twist therein. The bristles of the brush body are then trimmed to a uniform length in a trimmer 41, which can be a rotary trimmer such as employed in the prior art machines, or which can be a stationary trimmer that takes advantage of the fact that the brush body is rotating when it emerges from the wire twisting element of this invention. Because of this rotation, and'the continuous linear feed of the brush body, there is no need to rotatethe trimmer 41 as has been done in the past; the natural,

movement of the brush body will be sufficient in most instances Without any rotation of the trimmer. It should be noted also that the'trimmer does not necessarily have to follow the wire twisting element; it could be placed between the wire feed jaws and the wire twisting element if desired, thereby trimming the bristles beforethey enter the wire twisting element; It might, in fact, be desirable to do this in some applications where the bristles encounter appreciable drag in passing through the hol-- low member of the wire twisting element.

twisting force decreases as the bristles become softer and increases'as the space between the rods decreases,

' whereby the rods should in general be closer together for in its operation.

wires therotary forces would not be communicated to the soft bristles than for still bristles. The twisting force applied by rods 44 and 45 is communicated to the brush wires through the bristles, which are rigidlysecuredto the wires by the twist therein. Thus, the end result of this wire twisting arrangement also serves as an essential link If the bristles were not secured to the wires whereby the twist in the wires is a prerequisite to the twisting thereof. This means, of course,.that a short After being trimmed, the brush body is cut into the desired lengths by'cutting dies 42 and 43, which can be, actuated automatically by any suitable prior art actuators and control circuits. since the brush body is continuously driven, the cutting dies will momentarily interrupt its travel, so that the cutting dies should notbe located too close to the trimmer.

or wire twisting element. A large enough gap must be maintained to permit the brush body to bow out whenits travel is interrupted, without reflecting the interruption back into the wire twisting element, whose twisting effect" If the brush body must is dependent upon feed fate. be cut close to the trimmer, this is preferably accomplished by guiding the brush body around 'a turn after across the brush body and melts the wires thereof. With an electric arc cutter there would be no interruption of the brush feed, and the brush body could, accordingly, be

cut right nex'tto the trimmer. The apparatus for producing and timing this electric arc could be any suitable prior art welding circuit, and the arc could be flashed between a pair of electrodes which flank the brush body, or from one electrode to the wires, which are grounded at their feed jaws and storage reels. i I

It should be noted, however, that it is not necessary to cut the brush body in short lengths; it could be rolled up on large storage reels if desired, the reelsbeing 'rotated about one axis in synohronism with the brush feed rate and being rotated about another axis in synrchronism with the brush rotation. This canbe done, as well understood by those skilled in the art, by mounting the take-up reel in a gimbal structure which'allows the reel to simultaneously rotate about two perpendicular axes.

Referring to FIGS. 1 and 2, the progressive twisting battery of this particular embodiment comprises a rotating nod structure which worlrsagains't jaws 2.8 and 29 to produce a first increment of twist in the Wires, and a rotating It should be noted, though,'that length of brush must be twisted by hand to prime the :machine when it is initially placed in operation.

The rotating screw assembly, which rotates independent of and faster than the'rotatingrod assembly, comprises a helical screw 57 rigidly mounted on legs 58 within a cylindrical shell 59, which is journaled' to the rotating rod assembly by bearings so and 61.

The rotating screw assembly is supported by a pair of inwardly projecting coll'ars62 and d3, which are rigidly attached tO\ COlT6- spending end collars 46 and 2-7 of the rotating rod assembly. Cylindrical shell'59 is rotated by agear 64 on drive I shaft'd whichnieshes with'a gear 65 on cylindrical shell 59. Gears d4 and 65 are arranged to rotate the helical I screw 57 faster than the rods 44 and 45 therewithin at a speed selected'to (I) produce a desired linear brush feed rate and 2) a desired increment of twist, as explained more fully below. j

The mounting of rods 44 and iS within screw 57 is not essential to this embodiment of the invention, which could be arranged, as indicated in FIG. 4, by mounting rods and 45' in a separate cylindrical shell 66 which is spaced from cylindrical shell 59. In this case, cylindrical shell as would be supported independently of cylindrical shell 59 by means not shown, and would be driven through .a single gear s7 which meshes with a drive gear'dS, The

either can housed in this embodiment of the invention.

I The. twisting action of rods 44 and 45 is illustrated in FIGS. 9A, 9B, 9C and 9]), which show an untwiste brush body comprising wires and 21 with bristles 69 laterally disposedthereinbetween. As shown in these figures, wires 2% and 21 are twisted by force couples applied to wires 2% and 213. through bristles 69. In the example shown, the helical screw 5'7. is held stationary while the rods 44 and are rotated counterclockwise through a complete revolution. This rotates bristles 69, twists V wires 2t) and 21, and developsfeeding forces on bristles 69 as they rotate within the stationary screw. The spreading of the bristles in FIG. 913 results from the twist in the wires. Thus one method of generating simultaneous twisting forces and feed forces is to rotate rods 44 and 45 while holdinghelical screw 57 stationary.

Another method of generating simultaneous twisting and feeding fonces is to use a single rotating screw as shown in FIG. 5.. In this arrangement a helical screw 70 .lSlIlOUIlted within a cylindrical shell 71 on legs 72. When 5d and 51 to frame members 52 and 53 which are attached to or'form a part of a supporting framework not llOWlIl in the drawings. The rotating rod structure is i-riven by shaft 54, which is also journaled through bearlugs to frame members SZ'and 53, by means of identical irive gears 55 and 56, which mesh respectively with gears Jristles, and the speed at which the rods are rotated. The

screw is rotated, through meshing gears '73 and 74, the screw engages the bristles of a brush body therein and imparts simultaneous twisting and feeding forces The wires of the brush body, of course,. must be secured in wire guides or feed jaws which'develop a reacting force which allows the wires to be twisted. i In the two stage twisting arrangement shown in FIGS.

1, 2, and 4, rotating rods 44 and 45 Work against wire instead of working against fixed jaws the screw 57 works between the rotating rods and rotating screw. The specific speeds of rotation, and the specific screw pitch, will depend on the degree of twist desired in any particular application of this embodiment. The first increment of twist is determined by the speed of the rotating rods and by the feed rate. twist are determined jointly by the pitch of the screw, the rotary speed thereof, the diameter thereof, the stiffness of the bristles, the density of and smoothness thereof, and the diameter and twistability of the wires. however, the feed force decreases as the pitch of the screw coarsens while thetwist force increases, This relation can be better understood by considering the rotating rod structure to be a degenerate screw having an infinitely coarse pitch. Conversely, the feed force increases and the twist force decreases when the pitch is made finer, and both forces increase as the rotary speed is raised. Thus it can be said in general that the pitch and speed of the screw must be selected in lightof the particular brush materials used in a given application to produce the desired brush feed rate and twist. But in any event the rotary speed of the screw must exceed the rotary speed of the rods, md the difference between the two must be great enough to produce the desired twist increment and feed rate for the particular circumstances involved.

FIG. 7 shows a rotating fin structure which can be used in place of the rotating rod structures described above. The rotating fin structure contains longitudinal fins 78, 79 and 80 that project inwardly from a cylindrical shell 81 which is adapted to be rotated by means not shown. Since the bristles entering this structure will be spread, as shown in FIGS. and 9D, any suitable number of projecting fins can be used to engage the brush bristles. The optimum number of fins depends on the bristle stiffness in any given application; with relatively stiff bristles two or three fins are best, but with relatively soft bristles more fins are desirable.

FIG. 8 shows a rotating fin structure which can be used in place of the rotating screw structures described above. In this arrangement an inwardly projecting fin '75 is wound within a hollow cylinder 76 like one of the lands in a rifle barrel. Cylinder 76 is adapted to be rotated by a central gear 77, and it can be journaled and'driven as described above for the rotating screw structures. It

will be understood that this spiral fin structure generates simultaneous twisting and feeding forces in a manner analogous to the action of the rotating screws, and also that more than one spiral fin could be formed within the cylinder if desired. v

' FIG. 6 shows a different two-stage progressive twisting arrangement that can be used in the brush twisting machine of FIG. 1. In this arrangement a coarse helical screw 82 twists against the wire feed jaws and a fine helical screw 83 twists against the coarse helical screw. These screws are mounted in corresponding cylindrical shells 84 and 85, which are rotated in the same direction by corresponding gears 86 and 87. Screws 82 and 83 differ" not only in pitch, but also in the sense of their winding, i.e., the fine screw 83 is wound so as to feed the brush forward and the coarse screw 82 is wound so as to feed the brush backward. Since the fine screw 83 develops a larger feed force than the coarse screw 82, the brush will be fed forward at a rate determined by the difference in pitch of the screws, and the portion of the brush between the two screws will be in tension due to the backward feed effect of the coarse screw. This tension keeps the brush centered in the two cylindrical shells, and eliminates any tendency of the wire to wobble during the twisting process, as sometimes happens when a rotating rod or fin assembly is used in combination with a rotating The feed rate and the second increment of In general,

1% screw assembly. It should be noted that the screws of FIG. 6 are set up for a different direction of rotation than those shown in the other figures, but that they can be adapted for the other direction of rotation by simply reversing the twist of each screw. The screws can be driven at the same speed or at different speeds depending on their pitches, the particular brush materials involved, and the desired feed rate and degree of twist required in any specific application. It will be understood, of course, that spiral fin structures similar to the structure shown in FIG. 8 could be used in place of helical screws 82 and 83 without changing the fundamental operation. of this dual screw-twisting battery. In this case the pitch and feed direction of the spiral ledges would be chosen in accordance with the principles described above for screws 82 and 83.

FIGS. 3A and 3B show a stationary twisting-feeding ele-. ment which utilizes tangentially directed air jets to twist the wires and longitudinally directed air jets to feed the wires. This arrangement comprises a hollow cylinder 88 through which tangential channels .T and longitudinal channels L are drilled. An air chamber is formed around cylinder 88 by a concentric cylinder 89, and compressed air is delivered into the chamber through an air inlet 90. In this air drive arrangement the brush is supported by the air from the channels, thereby eliminating'all friction between the brush bristle and hollow cylinder 88. The structure does not necessarily contain both the longitudinal and tangential channels; with the longitudinal channels alone it makes a very useful feeding element which can be used to" provide or augment the feed force with the mechanical twisting elements of this invention.

In summary, the basic wire twisting element of this invention can be any suitable hollow member which is adapted to receive a twisted brush body and impart a 1'0- tary force to the wires thereof. Although several suitable members have been shown in the examples, they are by no means exhaustive of the basic form of this invention. With brushes which have very soft bristles, a simple rotating cylinder might be used without the rod, fin or screw elements shown in the examples. In this case the cylinder would be relatively small in diameter with respect to the brush body, to constrict the bristles thereof, and the rotary force would be applied from the inside surface of the cylinder to the relatively matted bristles therewithin. In brushes which utilize iron, steel or other ferromagnetic bristles, the rotary force could be generated 'no feed forces, can'be utilized in combination with any suitable prior art wire feed system'or with the air jet feed system of this invention.

From the foregoing description it will be apparent that this invention provides (1) a novel wire twisting element,

' (2) a novel wire feeding element, (3) a novel wire twistring-wire feeding element, (4) a novel wire and bristle feeder structure, (5) a novel-progressive wire twisting battery, and (6) a novel brush making machine formed by combinations of these novel structures. I

While the foregoing description sets forth the principles of the" invention in connection with specific apparatus, it is to be understood that this description is made only by way of example and not as a limitation of the scope of the invention as set forth in the objects thereof and in the accompanying claims, in which the word brush is defined to mean any brush-like article or structure, the word bristle to mean any relatively short transsimultaneously drawing a strand of wire through each of said wire feed jaws, and bristle feedermeans for depositing bristles between said stnands of wire in the space separating said wire feed jaws.

2. A brush wire twisting element comprising a hollow.

member adapted to receive a brush bodyzand to permit passage of said brush body therethrough, said hollow member having a'brush inlet endand; a brush outlet end, and means for applying a rotary twisting force to the 1 low members for mechanically engaging the bristles of J of said cylinders in the same direction with one of said ubody therethrough, a plurality of rigid longitudinal members rigidly attached to the interior of said first cylinder, a rigid helical screw rigidly attached to the interior of said secondcylinder, and means operable to rotate each cylinders being rotated faster thantheother.

wires of said brush body between said brush inlet and brush outlet ends of said hollow member.

3. A brush feeding element comprising a hollow memberadapted-to receive a brush body and to permit passage of said brush body therethrough, said hollow member having a brush inlet end and a brush outlet end, and means for applying a linear feed force to the wires of said brush body between said brush inlet and brush outlet ends of said hollow member. 1

4. A brush wire twisting and feeding element comprising a hollow member adapted to receive a brush body and to permit passage of said brush body therethrough, said hollow member having a brush inlet end and a brush outlet end, and means for applying a rotary twisting force and a linear feed force to the wires ofsaid brush body between said brush inlet and brush outlet ends of said hol low member.

5. A progressive brush twisting mechanism comprising first wire twisting means for applying a first rotary twist- A ing force to the wires of a brush body via the bristles thereof, reacting means for applying a first rotary reacting force to thewires of said brush body, said first'rotary reacting force being substantially equal'in magnitude tosaid first rotary twisting force but opposite in direction, second wire twisting means for applying a second rotary twisting force to thewires of saidbrush'body via the bristles'thereof, and said second rotary twisting force being greater in.

magnitude than said first rotary twisting force.

6. A brush twisting element comprising a pair-of hollow collar structures each adapted to receive a brush body and to permit passage of said brush body therethrough, a

pair of rigid longitudinal rods attached between said hollow collar structures, said collar structures being journaled for rotation about their longitudinal axes, and

means for rotating said collars and said rods about the longitudinal axis thereof. 1. V I

7. A brush feed element comprising a hollow cylinder adapted to receive a brush body and to permit passageof said brush body-therethrough, a plurality of air-channels formed in the walls ofsaid hollow cylinder, said air-chaniels being directed along the longitudinal axis of said holow cylinder, and means for guiding compressed air into '11. A progressive brush twisting device comprising first and second rotatable cylinders each adapted to re-, ceive a twisted brush body and to permit passage of said brush body therethrough, a first nigid helical screw. rigidly attached to the interior of said first cylindena second rigid helical screw attached to the interior of said second cylinder, said first helical screw being wound in one direction and said secondhelical screwbeingwound'in the other direction, the pitch of said first helical screw differing from the pitch of said second helical'screw, and means for rotating @3101) of said cylindersin the same direction.

12., A'brush wire and bristle feeder device comprising a plurality of spaced iwire feed jaws, a source of Wire corresponding to each' of said wire feeder jaws, means adapted to guide the wire from each of said wire sources to the corresponding wire feed jaw, means operable to simultaneously draw: wirefrom eachof said feed jaws, and bristle feeder means operable to deposit bristles between "said wires in the space separating said wire feed jaws.

14; A brush making machine as defined inclaim 13 and also including wire guide means associated with each ofsaid wire strands, saidwire guide means being operable to bring said strands of wire together in substantially parallel alignment, and said wire guide means being adapted to oppose said twisting force developed bysaid wire twisting means.

15.A brush making machine as defined in claim'14,

'wherein said wire guide means contains a plurality of spaced wire feedjaws, said wire feed jaws being adapted to oppose said twisting force developed by said wire twisting means, and wherein said bristle feeder means is .wherein said wire twisting means comprises a hollow member adapted to receive said wires and said bristles :aid air-channelsfrom the outside of said hollow cylin- V ler.

8. A brush twisting and feeding element-comprising l. hollow cylinder adapted to receive a brush body and 0 permit passage of said brush body therethrou'gh, a plu- 1 'ality of air channels formed in the walls of said hollow :ylinder, said air-channels being directed across the longiudinal axis of said hollow cylinder 'and along thelongitu-I wherein said wire feed jaws are located between said wire sources and said wire twisting means, and wherein said wires and'said bristles are fed from said wire feed jaws through said hollow member of said wire twisting means,

, and ,wherein' said wire twisting means is operable to twist 'eceive a' twisted brush body and to permit passage of said arush body therethrough, means within each'of said holchannelrand wherein said' wire feed channels are each curved in one plane to accommodate the twist produced 'in said'wires, by said twisting means and wherein said v 13 1 7 wire feed channels are skewed with respect to each other to oppose said twist, in said wires.

19. A brush making machine as defined'in claim 18, wherein said wire twisting means is adapted to apply a linear wire feed force to said wires through said bristles.

20. A brush making machine as defined in claim 19, and also including second Wire twisting means for applying a second rotary wire twisting force to said wires through said bristles thereof.

21. A method for making a twisted wire brush or the like, comprising feeding adjacent wires with brush material therebetween through a twisting station while simultaneously applying a force to the brush material in a direction to impart a twist to said wires, thereby locking the brush material between said wires.

22. A method for making a twisted wire brush comprising feedingbristles between adjacent'strands of continuously moving Wire, applying a force to said bristles in a direction to impart a twist of said Wires to lock said bristles therebetween.

References Cited in the file of this patent UNITED STATES PATENTS Marks Sept. 8, 1959 

1. A BRUSH WIRE AND BRISTLE FEEDER MECHANISM COMPRISING A PLURALITY OF SPACED WIRE FEED JAWS EACH ADAPTED TO ACCOMMODATE A STRAND OF WIRE, WIRE FEEDER MEANS FOR SIMULTANEOUSLY DRAWING A STRAND OF WIRE THROUGH EACH OF SAID WIRE FEED JAWS, AND BRISTLE FEEDER MEANS FOR DEPOSITING BRISTLES BETWEEN SAID STRANDS OF WIRE IN THE SPACE SEPARATING SAID WIRE FEED JAWS.
 9. A PROGRESSIVE BRUSH TWISTING DEVICE COMPRISING FIRST AND SECOND HOLLOW, ROTATABLE MEMBERS EACH ADAPTED TO RECEIVE A TWISTED BRUSH BODY AND TO PERMIT PASSAGE OF SAID BRUSH BODY THERETHROUGH, MEANS WITHIN EACH OF SAID HOLLOW MEMBERS FOR MECHANICALLY ENGAGING THE BRISTLES OF SAID BRUSH BODY, AND MEANS OPERABLE TO ROTATE EACH OF SAID HOLLOW MEMBERS. 